The present invention relates to a driving circuit for a liquid crystal display and, more particularly, to a driving circuit for an active matrix type liquid crystal display, which is simple in its construction and suitable to be fabricated in an integrated circuit device.
The panel display of an active matrix liquid crystal is controlled by a driving circuit to which digital image or video signals are inputted.
In a conventional driving circuit for a liquid crystal display, the number of output transistors had to be increased accordingly with an increase in the number of gradations of brightness. Assuming here that the necessary number of gradations was 16 and the number of stages was 100, the number of output driver transistors required was 1,600. The use of such a driving circuit in an integrated circuit device results in not only a large chip area therefor but also a high manufacturing cost. Further, such a circuit having a large number of the output driver transistors required the power supply circuit having a larger driving capability increased proportionally to the number of gradations.